(
;
GM[1]
US[jansteen@cwi.nl (Jan van der Steen)]
VW[]
SZ[19]
PW[SQUID] WR[5k*]
PB[5ocean] BR[4k*]
DT[1993-03-25]
PC[IGS]
RE[Void]
C[An unfinished game on IGS
Hi Jan,
Recently I have been reading a "Selected Openings" by Go Seigen, and
I learned a tesuji to seal a corner from outside. I have used it
twice in real games on IGS. The first time I made one move wrong
and the seal wasn't perfect and later seemed to cost me the game.
The second time seemed to be a great success (I understood that
move this time), but the game was adjourned after about 100 moves.
Luckily I remember the moves, and I would like to ask your comments.
I made some brief comments too.
BTW, I feel this is a good chance to tell you yet another alias of
mine, and I did it in the game comments. :-)
Thanks in advance,
Kind regards, Jim ]
;
B[pd]
;
W[dp]
;
B[pq]
;
W[dc]
;
C[Chinese Fuseki.]
B[qk]
;
W[nc]
;
L[pf][kd]
C[
(Jan & Kishiko:)
Highly unusual, normal moves are (a) or (b).]
B[nd]
;
W[md]
;
L[od]
C[This is the tesuji Go Seigen used in a game of his. This
is a common way to seal the corner, he said.
Previously I only knew to play O15 in this case, but Go Seigen taught
me something I really like.
(Jan & Kishiko:)
In the game white played (a). The variations show another possibility
for whites next move.]
B[mc]
(
;
W[od]
;
B[ne]
;
W[oc]
;
B[oe]
;
W[pc]
;
C[This double hane is important. Without a good understanding
I could easily make R16 instead. And that what I did in another game.
(*** 'B' to see this variation.)]
B[qc]
(
;
W[qd]
;
B[pe]
;
W[qb]
;
B[rc]
;
C[Again, it seems that a move at the corner is a blind spot
to players of my level. An S18 here is sente for W. (See variation
for white's alternative (s18)).]
W[lc]
(
;
B[mb]
;
W[lb]
;
B[ld]
C[
(Jan & Kishiko:)
Interesting, you could also preserve this move (it's bad
aji for white) and play (s18) immediately.]
;
W[me]
;
B[mf]
;
W[le]
;
B[lf]
;
C[See, this time, I got a wall that looks more solid.]
W[ke]
;
C[Maybe I should play S18 first. :-)
(Jan & Kishiko:)
We think that you should push once more at (a).]
B[jp]
L[kf]
;
W[qi]
;
B[pj]
C[
(Jan & Kishiko:)
Better attack with keima at (a) (proverb: attack with keima,
escape with ikken-tobi :-)]
L[oj]
;
W[pi]
;
B[oi]
;
W[rk]
;
B[rl]
;
W[rj]
;
B[pl]
C[
(Jan & Kishiko:)
Bad shape (also shown in the game I think). Better connect
solidly with (a).]
L[ql]
;
C[To be frank, I was thinking to force W to live small here.]
W[qf]
;
B[qe]
;
W[oh]
;
B[pg]
C[
(Jan & Kishiko:)
This is not good, just hane at (a) seems to be normal move.]
L[nh]
;
W[ph]
C[
(Jan & Kishiko:)
Probably better at (a), now your previous move forced bad
shape.]
L[qg]
;
B[nh]
C[
(Jan & Kishiko:)
Better capture at (a) and attack the whole group. The lower
corner will turn into territory automatically.]
L[qg]
;
W[og]
;
C[Actually, if W played S18 now (instead of P13, for example),
I would probably play S14 to give up those two stones.
(Jan & Kishiko:)
Agree.
]
B[rb]
;
W[pb]
;
B[rf]
C[
(Jan & Kishiko:)
We would have played (a), but your move also seems to work.]
L[qg]
;
W[ng]
;
B[mh]
;
W[mg]
;
B[lg]
;
W[qg]
;
B[rg]
;
W[rh]
;
C[Now W is dead. But you never know...]
B[pf]
;
L[lh][nj]
C[
(Jan & Kishiko:)
Funny move! Better cut at (a) (black (b)) and then this
move.]
W[nf]
;
B[lh]
;
C[W seems desparate.]
W[rm]
;
B[sl]
;
W[qm]
;
B[ql]
;
W[qp]
;
C[I was thinking to play Q4. But I was not willing to let W
live too easily here. :-)
(Jan & Kishiko:)
This direction is correct Jim.]
B[qq]
;
W[pp]
;
B[op]
;
W[oo]
;
C[
(Jan & Kishiko:)
Just nobi is better, this somehow helps white to make shape.]
B[no]
;
W[oq]
;
B[np]
;
L[rq][rr][ro]
C[
(Jan & Kishiko:)
Bad, better play hane at (a) (hane + connection is sente
for white). That's why nobi was better to avoid this.]
W[on]
;
C[Good!]
B[rp]
;
W[ro]
;
B[rq]
;
C[To here, I thought I had made some regretable moves. Now
P10 cut is exposed.]
W[nn]
;
B[pm]
;
W[pn]
;
B[qo]
;
W[po]
;
C[I thought about O8, but finally decided to go with N6. Maybe
this choice was wrong.
Yes one should push opponent's stones towards own thickness. But
with P10 cut, it might not be so thick there...
(Jan & Kishiko:)
Better just jump to (o8) is better. If you attack a group you should
try to keep a distance and also to keep your positions strong.]
B[mn]
;
W[mm]
;
B[ln]
;
W[nq]
;
B[mq]
;
W[oj]
;
B[nl]
;
W[lm]
;
C[Again a tough decision. I also thought about N9 or O11 to
make sure the upper W team is captured, and then chase this lower
W team...
Maybe O7 is too hasty and too greedy.
(Jan & Kishiko:)
Agree, maybe (o11) is better. But it's difficult.]
B[nm]
;
W[ni]
;
C[B still looks good to me here.]
B[lk]
;
W[mk]
;
L[mj]
C[Maybe not a good move. Should be N8? Yes, N8. If W M10
next, B can L10, I think.
(Jan & Kishiko:)
Maybe black (a) instead ?!]
B[lj]
;
W[ml]
;
C[Suddenly I found Q8 group is in danger, but I finally made
up my mind and played L6.]
B[kn]
;
W[km]
;
B[jm]
;
W[sk]
C[I found if W R6 (instead of T9) to make a solid eye, B teams
could be in great danger.]
;
C[This move kills W, I think. But now the upper W team lives.
The game is adjourned here. I came very close to deliever a decisive
blow, but now it seems to be still playable for W.
B is still better, isn't he?
(Jan & Kishiko:)
It's difficult. Since the upper white group can live, the black center
group is weak now. It's still an open game to us.
(*** end of unfinished game ***)]
B[so]
;
)
(
;
Name[White (s18)]
AddEmpty[lc]
AddW[rb]
C[
(Jan & Kishiko:)
If white plays (s18) then maybe black can play like...]
;
B[nb]
C[
(Jan & Kishiko:)
Now white has a difficult choice, both (a), (b) and (c)
are somehow possible. Maybe most likely is (a) (which is shown).]
L[ob][mb][rd]
;
W[ob]
;
B[oa]
;
W[pb]
;
B[mb]
;
W[rd]
;
B[re]
C[
(Jan & Kishiko:)
End of variation. Black has sealed white in from both sides.
A success!]
)
)
(
;
C[I made R16 in that game instead...]
AddEmpty[qc]
AddB[qd]
Name[variation]
;
L[ld][pe]
C[Would this move be better at R17?
(Jan & Kishiko:)
We think so, especially
since the ladder at (a) is unfavorable to black, and (r17) creates
a cut at (b).]
W[lc]
;
B[mb]
;
W[lb]
;
C[I was happy to get R17.]
B[qc]
;
W[qb]
;
B[rb]
;
W[pb]
;
B[me]
;
C[To here, I thought I got a solid wall. But later in the game,
somehow the cutting point at Q15 gave me trouble.]
W[ld]
;
C[(*** end of variation.) (*** '(' to continue.)]
B[fq]
)
)
(
;
L[qc][lc]
C[
(Jan & Kishiko:)
This move should also be expected when playing the cross-cut
variation at B(n17). The aim of this kosumi is two folded: White
aims at (a) in the corner, and (b) to capture the cutting stone.
Blacks answer is difficult since it has to take care of both treaths.
Where to play next with black?]
W[ob]
Name[A variation]
;
C[
(Jan & Kishiko:)
This (funny looking) move is the correct answer. It protects
the corner and...]
B[pc]
;
C[
(Jan & Kishiko:)
...if white tries to force black into bad shape...]
W[ne]
;
C[
(Jan & Kishiko:)
...black has this tesuji on his sleeve!]
B[nb]
;
W[od]
;
B[oc]
C[
(Jan & Kishiko:)
Possible since black has a stone at (q17).]
;
W[nd]
;
C[
(Jan & Kishiko:)
White is locally destroyed. The black corner is more than
satisfying, and the compensation white got is not called thickness
but a heavy group of stones.]
B[mb]
)
(
;
W[ob]
C[
(Jan & Kishiko:)
This is the same diagonal move as the previous variation.]
Name[Expected...]
;
C[
(Jan & Kishiko:)
The (funny) shape move by black.]
B[pc]
;
C[
(Jan & Kishiko:)
Since white can capture the cutting stone, he normally will.]
W[lc]
;
C[
(Jan & Kishiko:)
Sacrifice two stones instead of one is basic techniques to
create more forcing moves.]
B[mb]
;
W[lb]
;
C[
(Jan & Kishiko:)
First kikashi...]
B[me]
;
W[ld]
;
C[
(Jan & Kishiko:)
A clever move making the stone at (q17) work better.]
B[nb]
;
W[oc]
;
B[od]
;
W[pb]
;
B[qb]
;
L[ne][qc]
C[
(Jan & Kishiko:)
End of variation.
The black corner has a strong shape although still two cutting points
(at (a) and (b)).
This diagram shows that black shouldn't play this variation under
all circumstances since white gets quite strong at the upper edge
too. Normally black is only willing to give white this strong shape
when the resulting strength along the upper edge is overconcentrated.
(See the variation)]
W[ma]
;
Name[Overconcentrated]
B[de]
C[
(Jan & Kishiko:)
Imagine that black played here before...]
;
W[ce]
;
B[cf]
;
W[cd]
;
B[df]
;
W[fc]
;
B[dj]
Mark[fc]
L[ed][fd][ec][ge]
C[
(Jan & Kishiko:)
The position in the diagram would be a great succes for black
since the marked white stone is too low (inefficient) in this position.
That stone should be at (a) or (b).
Later black can make white even more overconcentrated by playing the
sequence (a), (c), (d). This sequence will enlarge the black
influence on the left edge and flatten whites position.]
;
)
)